Make SpeciesVariant virtual

src/Library/CreatureData/SpeciesVariant.hpp

@@ -32,7 +32,7 @@ namespace CreatureLib::Library {
                        std::vector<std::string> talents, std::vector<std::string> secretTalents,
                        const LearnableAttacks* attacks);
 
-        ~SpeciesVariant();
+        virtual ~SpeciesVariant();
 
         inline const std::string& GetName() const { return _name; }
         inline float GetHeight() const { return _height; }